Engine.



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T. F BRACKETT,

ENGINE.

APPLICATION FILED MAY 18. 1918.

Patented Oct. 22, 1918,

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ENGINE. APPLICATION FILED MA1B.|9IB.

Patented Oct. 22, 1918,

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ENGINE.

APPLICATION FILED MAY 18. 1918 Patented Oct. 22, 1918.

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ENGINE.

APPLICATION FILED MAY 1B. 1918.

1,282, Patented 0%. 22, 1918,

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MAGY F. BRACT'KETT, (3F CHICAGO, ILLIHOIS.

ENGINE.

resales.

specification of Letters Patent.

Patented (lot. 22, 1918.

Original application filed February 20, 1918, Serial No. 218,35. Divided and this application filed may 18,

To all whom it may concern:

Be it known that 1, Tuner Baaorrnrr, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, having invented a certain new and useful Improvement in Engines, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

This invention relates to improvements in engines and is especially concerned with improvements in internal combustion engines of that type in which a plurality of cylinders are arranged to move bodily about a common axis, which is parallel to the axes of the cylinders, the piston. rods of the cylinders being connected to an angle plate which rotates about an axis disposed at an angle to the axis about which the cylinders rotate.

This application is a division of my copending application Serial 218,3s5, filed February 20, 1918.

The objects of my invention are:

First: to provide an engine of the type referred to which operates in a new and more efficientmanner than engines of the same type which have heretofore been com structed Second: to provided an engine of the type referred to having a stationary shaft for supporting the rotating cylinders, and a power shaft in alinement with said stationary shaft, said power shaft being connected to rotate with the cylinders; and

Third: to -provide novel valve operating mechanism in an engine of this type of such a character that the length of the engine may be reduced as compared with engines of this type which have heretofore been constructed, without increasing the diameter of the engine. I

Other objects, adaptabilities. capabilities and modifications will appear as the description proceeds, reference being had to the accompanying drawings, in which:

Figure 1 is a central longitudinal section of my improved ei'zgine. showing certain of the parts in side elevation;

Fig. 2 is an enlarged fragmentary longitudinal section taken through the valve gear and the casing therefor at the left hand end of my improved engine as shown in Fig. 1;

Serial No. 235,401.

Fig. 3 is an enlarged fragmentary section taken on the same plane as Fig. 2 but show Fig. 7 is a fragmentary section taken on line 77 of Figs. 2 and 3;

Fig. 8 is a section taken on line 88 of Fig. 1, showing the intake and exhaust valves and the lever mechanism for operating these valves; and

Fig. 9 is a fragmentary longitudinal section through the valve operating mechanism and casing at the right hand end of my engine as shown in Fig. 1.

The several sections are taken on the lines indicated by the small arrows and similar characters of reference refer to similar parts through the several. views.

In my co-pending application above referred to I have described my improved r0- tary engine in detail, and I will therefore describe only those portions of my invention which it is necessary to describe in order to clearly set forth the structure and. mode of operation of my improved valve operating mechanism.

Referring to the drawings, the reference character 20 indicates the stationary shaft of my improved engine, the outer end of which is anchored to a suitable support 21. This shaft comprises two longitudinally spaced alined hearing portions 22 and 23 respectively and an intermediate angularly disposed bearing portion 24 upon which the angle plate 25 is rotatably mounted. P.0- tatably mounted upon the bearing portions 22 and :23 respectively are a pair of cylinder carriers 26 and 27 respectively in which the inner opposed ends of pairs of alined cylinders 28 are secured. Slidably mounted in each pair of alined cylinders is a double ended or trunk piston 29; These trunk pistons are connected with the crank pins 30 secured to the angle plate by means of pit man rods 31, the head ends of which are secured to one end of the trunk pistons by universal joints 32,,and the crank ends of which are secured to the pins 30 by means of a ball and socket connection indicated in general by the reference character 33. A bevel gear 3% is secured to rotate with the cylinder carrier 26 by means described in detail in my co-pending application above referred to, and meshes with a second bevel gear (not shown) which is secured to the angle plate 25.

From the above description it will be clear to those skilled in the construction of engines of this type that when the pistons reciprocate in the cylinders in the proper order the angle plate 25 will be caused to rotate about the angularly disposed. bearing portion of the stationary shaft, and that this rotary motion of the angle plate will be communicated to the cylinder carriers through the bevel gear 34. In this manner the proper relation between the angle plate and the cylinders will be maintained.

Tn engines of the type to which my engine belongs the mechanism for operating the in take and exhaust valves, has, so far as I know been located at the outer ends of the cylinders. Such a construction increases the length of an engine to an undesirable degree. In order to reduce the overall length of the engine I place the gear operating mechanism between the cylinders and the adjacent shaft portions. To thus place the gear operating mechanism without increas-' ing the diameter of the engine I have found it necessary to design an entirely new type of valve operating mechanism, which I will now describe in detail.

Referring to Figs. 1 and 8, it will be noted that each cylinder is provided with two exhaust valves 35 and a single intake valve 36. These valves are of t is usual puppet valve construction comprising the compression springs 37 for closing the valves. The means for opening the exhaust valves comprise the rock levers 38 which are pivotally mounted upon bosses 39 extending from the branches 40 of the intake manifold ll. The inner ends 42 of these levers are engaged by the outer ends of the pushrods 43. which are mounted to reciprocate in the enlarged inner end 4.4 (see Fig. 2) of the rotary shaft 15. This end of the rotary shaft is secured to the valve housing or casing 46 in any suitable manner and the valve housing 46 is secured to the cylinder carrier 26 in any desirable manner, as for instance by means of screws 47. Suitable packings 48 and glands as are used to prevent the lubricating oil from leaking outward. along these pushrods. The intake valves 36 are each provided with a rocker arm 50 which has a shaft extension extending through a bearing formed in a boss 51 on the inner side of each branch of the intake manifold, thus forming'a shaft for the rocker arm 50. A rocker arm 52 is keyed to the opposite 'end of the shaft extension of the rocker arm 50,

a awni awe as shown in Fig. 1, and is actuated by one of the inner pushrods 53 which are likewise mounted to reciprocate in the enlarged inner end of the shaft 45, as shown in Fig. 2, and are also provided with packings and glands to prevent the leakage of the lubricating oil along the pushrods.

From the above description it will be understood that the intake and -exhaust valves will be opened and closed in the proper sequence if the pushrods 43 and 53 are reciprocated in the proper sequence.

Referring to Fig. 2 it will be noted that the inner ends of the pushrods are bifurcated and provided with alined bearing apertures for receiving the shafts 54 of the rollers 55. The cam plate 56 is provided with an outwardly extending boss 57 which projects into a recessin the inner end of the rotary shaft 45, and is rotatably mounted therein by means of ball bearings 58. The cam plate 56 is provided with two concentric series of cams 59 and 60 (see Fig. 7). The outer series of cams 59 actuate the pushrods 43 and the inner series of cams oper ate the pushrods 53. The cams 59 and 60 are displaced from each other angularly in such a manner that the intake valves will be opened immediately after the exhaust valves are closed.

There are three cams for operating the exhaust valves and three cams for operating the intake valves. The cam plate 56 is driven through the internal gear 61 which is secured to the inner'periphery of the housing s6. The gear 61 will therefore revolve in synchronisrn with the cylinder carriers and the cylinders. A spur gear 62 is eccentrically mounted upon the end of the stationary shaft 20 and meshes with the teeth of the internal gear 61. A compensating plate 63 is also eccentrically mounted upon the end of the shaft 20 and is pro vided with a pair of oppositely extending radial slots 64: and 65 respectively, the two slots lying upon opposite sides of the plate. The eccentricity of the plate 63 is one half the eccentricity of the spur gear 62; that is, the center of the plate 63 lies half way between the center of the gear 62 and the center of the shaft 20. A driving pin 66 is scoured to the spur gear 62 adjacent its periphery and entends into the slot 64. The pin 66 is provided with an anti-friction roller 67 which engages the sides of the slot 6%. A driven pin 68 is secured to the cam plate 56 adjacent its periphery and extends into the slot 65 of the compensating plate 63, and is likewise provided with an antifriction roller 67. The spur gear 62 and the compensating plate 63 are provided with suitable roller bearings 69 and 70 respectively.

From the above it will be clear that as the cylinders rotate about the axis of the nasaieo shaft 20 the cam plate 56 will likewise be rotated about the same axis and in the same direction as the cylinders; and that consequently it is necessary to provide some means for causing the cam plate to rotate at a greater rate of speed than that of the cylinders, in order that the same may advance relatively to the rollers 55, and thereby operate the pushrods. If the cam plate 56 were merely provided with one cam for operating the exhaust valves and one cam for operating the inlet valve, it would be necessary for the cam plate to make three revolutions for every two revolutions of the cylinders to enable it to actuate the valves of all seven cylinders during two revolutions of the engine, but since I have provided the cam plate with three cams for actuating each set of valves, it is only necessary that the cam plate gain one-third of a revolution during two revolutions of the engine, or one-sixth of a revolution during one revolution of the engine. I accomplish this by making the gear ratio of the gears 61 and 62, seven to six. Since the gear 62 is eccentrically mounted relative to theshaft 20 and the cam plate 56, it is impossible to drive the cam plate 56 directly from this gear by means of the ordinary slot and pin connection, and at the same time drive the cam plate 56 at a constant angular velocity, assuming that the engine is rotating at a constant angular velocity. As it would be undesirable to give the cam plate a variable angular motion'relative to thepushrods, I interpose the compensating plate 63 between the gear 62 and the cam plate. By giving this compensating plate half the eccentricity of the gear 62 the pins 67 and 68 will slide in the slots 6 and 65 respectively in such a manner that the-cam plate 56 will be driven at an angular velocity constantly proportional to the velocity of the cylinders or the angular velocity of the push rods.

While engines of this type have heretofore been provided with gear driven cam plates and similar constructions-for operating the valves of the engine, so far'as I am aware all of these constructions involved a gear train having a'shaft lying eccentrioally of the engine shaft and at such a distance therefrom that it is impossible to place the valve driving mechanism between the cylinders without moving the cylinders outwardly from the axis of the shaft and thereby considerably enlarging the diameter of the engine. With my construction all of the rotating elements of the valve operating mechanism are substantially concentric with the shaft.

20 and on account of this fact I am enabled to place this gearing between the cylinders without in any Way increasing the diameter of the engine. The importance of this improvement lies in the fact that the length of-the engine can be reducedwithout making it necessary to increase the diameter of the engine. This is an important consideration, for the reason that I have designed my engine for use in airplanes, where it is .very desirable to keep the diameter of the engine within the smallest possible limit.

While I have fully described a valve operating mechanism at the left hand end of my invention, as shown in Fig. 1, the details of this mechanism for the opposite side of the engine are substantially the same except that the spur gear 62 is rotatably mounted upon an eccentric 71, shrunk or otherwise secured to the stationary shaft 20 and the compensating plate 63 is rotatably mounted upon an eccentric 72 similarly secured to the shaft 20, the eccentricity of the eccentric 72 being half the eccentricity of the eccentric 71. The cam plate 56' is also rotatably mounted upon the. shaft 20 and en gages rollers 55 to actuate the pushrods 43 and 53 in just the same manner in which the pushrods 43 and 53 are operated.

While I have described the details of the preferred embodiment of my improved valve operating mechanism, it is to be understood that it is capable of other adaptations and modifications within the scope of the appended claims. I

Having thus described my invention, what I claim is:

-1. A rotary engine comprising a stationary shaft and a rotary shaft arranged in alinement and having opposed ends, a plurality of cylinders mounted to rotate about the axes of said shafts and having their axes parallel with said axes, valves for said cylinders, operating mechanism for said valves, comprising a plurality of pushrods, means rotating with said cylinders for reciprocatingly supporting said rods parallel with said shafts and .in circles concentric with said shafts including a cam plate, and means for rotating said cam plate comprising an external gear eccentrically mounted on the opposed end of said stationary shaft, an internal gear meshing therewith and rotating with said cylinders, a compensating plate rotatably mounted on said stationary shaft, and having half the eccentricity of said external gear, the said compensating plate having a radial slot on one side and a radial slot on the other side extending in the opposite direction from said first named slot, a pin secured to said eccentric gear and sliding in the adjacent slot, and a pin secured to said cam plate sliding in the other of said slots.

2. The combination with a stationary carrying said rods to rotate with said cylinders, a cam plate for actuating said rods, mounted to rotate about the axis of said shaft, means for rotating said cam plate, comprising an external gear eccentrically mounted on said shaft, an internal gear meshing with said external gear and rotatable with said cylinders about the axis of said shaft, and means connecting said external gear and camplate for driving said cam plate at an angular velocity constantly proportional to the angular velocity of said internal gear.

3. The combination with a shaft, of a plurality of cylinders mounted to rotate about the axis of said shaft, and having their axes parallel therewith, valves for said cylinders, valve actuating mechanism comprising a plurality of pushrods arranged about the axis of said shaft, a cam plate for actuating said pushrods mounted to rotate independently of said cylinders, and means for rotating said cam plate comprising an external gear rotatably and eccentrically mounted on said shaft, an internal gear meshing therewith and driven by said cylinders, and means rotatably mounted on said shaft for driving said cam plate from said external gear at an angular velocity constantly proportional to the angular velocity of said cylinders.

l. The combination with a shaft, of a plurality of cylinders mounted to rotate about the axis of said shaft, valves for said cylinders, valve actuating mechanism comprising a plurality of pushrods arranged about the axis of said shaft, a cam plate for actuating said pushrods mounted to rotate independently of said cylinders, and means for rotating said cam plate comprising an external gear rotatably and eccentrically mounted on said shaft, an internal gear meshing therewith and driven by said cylinders, and means rotatably mounted on said shaft for driving said -cam plate from said external gear at an angular velocity constantly proportional to the angular velocity of said cylinders.

5. The combination with a shaft, of a plurality of cylinders mounted to rotate about the axis of said shaft, valves for said cylinders, valve actuating mechanism comprising a plurality of pushrods, a cam plate for actuating said pushrods mounted to rotate independently of said cylinders, and means for rotating said cam plate comprising an external gear rotatably and eccentrically mounted on said shaft, an internal gear meshing therewith and driven by said cylinders, and means for driving said canr plate from said external gear at an angular velocity constantly proportional to the angular velocity of said cylinders.

6. The combination with a shaft, of a plurality of cylinders niountedio rotate about naeasso cylinders.

'7. The combination with a shaft, of a plurality of cylinders mounted to rotate about the axis thereof, of valves for said cylinders, and means for actuating said valves comprising a rotatable cam plate, a rotatable member for driving said cam plate, having its center eccentric to said cam plate, driving connections between said cylinders and said rotatable member, and a compensating plate rotatably mounted between said cam plate and rotatable member and having a slot and pin connection with each of said members respectively.

8. The combination with a shaft, of a plurality of cylinders mounted to rotate about the axis thereof, of valves for said cylinders,

and means for actuating said valves comprising a rotatable cam plate, a rotatable member for driving said cam plate, having its center eccentric to said cam plate, driving connections between said cylinders and said rotatable member, and driving connections between said rotatable member and said cam plate for driving said cam plate at an angular velocity constantly proportional to the angular velocity of said cylinders.

9. The combination with a shaft, of a plurality of cylinders mounted to rotate about the axis of said shaft, said cylinders being spaced from said shaft, valves for said cylinders, means for actuating said valves, comprising a plurality of pushrods reciprocatingly supported parallel to said shaft, and driving connections between said cylinders and said rods for reciprocating the latter, said driving connections lying entirely between said cylinders.

10. The combination with a shaft, of a plurality of cylinders mounted to rotate about the axis of said shaft, said cylinders being spaced from said shaft, valves for said cylinders, means for actuating said valves, comprising a multiplying gear train, the center of the gears of said train lying within the periphery of said shaft.

11. The combination, with a shaft, of a plurality of cylinders mounted to rotate about the axis of said shaft, and having their axes parallel thereto, valves for said cylinders, and mechanism for actuating said valves, comprising a multlplying gear train. wholly between said cylinders.

12. The combination with a shaft, of a plurality of cylinders mounted to rotate about the axis of said shaft, and having their axes parallel thereto, valves for said cylinders, and mechanism for actuating said valves, comprising a gear train lying \vholly between said cylinders.

' 131 The combination with a shaft, of a plurality of cylinders mounted to rotate about the axis of said shaft, and having their axes parallel thereto, valves for said cylinders, and mechanism for actuating said valves comprising an external gear meshing with an internal gear.

14. The combination with a shaft, of a plurality of cylinders mounted to rotate about the axis of said shaft, and having their axes parallel thereto, valves for said cylinders, and mechanism for actuating said valves comprising rotatable driving and 1 p at this patent may be obtained tor ave cents each, by addressing the driven member having different centers and means for connecting said members for rotating said driven member at an angular velocity constantly proportional to the angular velocity of said driving member.

15. The combination with a shaft of a plurality of cylinders mounted to rotate about the axis of said shaft, valves for said cylinders, and mechanism for actuating said valves comprising means lying Wholly between said cylinders for changing the rotary motion of said cylinders into reciprocatory motion.

In witness whereof, I hereunto subscribe my name this 14th day of May, 1918.

TRACY F. BRACKETT.

Commissioner of Patents,

Washington, D. 0. 

